(19) |
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(11) |
EP 0 228 136 A3 |
(12) |
EUROPEAN PATENT APPLICATION |
(88) |
Date of publication A3: |
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21.03.1990 Bulletin 1990/12 |
(43) |
Date of publication A2: |
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08.07.1987 Bulletin 1987/28 |
(22) |
Date of filing: 18.12.1986 |
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(51) |
International Patent Classification (IPC)4: G09G 1/16 |
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(84) |
Designated Contracting States: |
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DE FR GB IT |
(30) |
Priority: |
30.12.1985 US 815362
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Applicant: Philips Electronics N.V. |
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5621 BA Eindhoven (NL) |
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(72) |
Inventors: |
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- Kaplinsky, Cecil Hertz
NL-5656 AA Eindhoven (NL)
- Li, Jan-Kwei Jack
NL-5656 AA Eindhoven (NL)
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(74) |
Representative: Strijland, Wilfred et al |
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INTERNATIONAAL OCTROOIBUREAU B.V.,
Prof. Holstlaan 6 5656 AA Eindhoven 5656 AA Eindhoven (NL) |
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(54) |
Abstract operation-signalling from a raster scan video controller to a display memory |
(57) A generalized operation-signalling logic for a raster scan video controller whereby
the video controller, in accessing the memory of a computer system, can indicate what
type of operation is to be performed at each memory address to be accessed. The signalling
scheme provides a rich set of functions, logic to generate this signalling and an
external PLA-type device which interprets this signalling for a wide variety of memory
types.